There is a general desire in the population for people to have white or whiter teeth. Such white teeth are an indication of good health and in particular good oral health care. A problem is that various foods and the use of tobacco will discolor and stain teeth. Beverages such as coffee, tea, and soda can also discolor and stain teeth.
Scientists are continuously searching for effective teeth whitening and stain removal demonstrations to support marketing and scientific research needs. Several whitening demonstrations have been developed previously. One such demonstration uses stained sand dollars as a substrate to demonstrate the whitening efficacy of a particular toothpaste. The sand dollars are first stained and are then brushed with both the toothpaste being evaluated and a control toothpaste. The scientists and/or consumers may then visually compare the sand dollar(s) brushed with the two different toothpastes for different whitening effects in order to demonstrate higher whitening efficacy of a particular toothpaste. This demonstration may show the advantage of a toothpaste in removing both external and internal stains.
A second demonstration also uses stained shells as a substrate. The second demonstration aims to show that more stains may be removed from a stained shell by dipping the stained shell in a toothpaste slurry with agitation than by dipping it in a non-toothpaste solution with agitation. Since the toothpaste contains at least one surfactant and the non-toothpaste solution does not, the second demonstration aims to show that, with simple agitation, a toothpaste slurry with at least one surfactant may remove more stains than a non-toothpaste solution that does not contain surfactant.
It is desirable to develop further demonstrations in order to help evaluate the whitening and stain removal efficacy of new products and compositions, such as new toothpaste formulations, or to help aid consumer decisions about toothpaste purchases.